Use of cell cycle analysis to characterise growth and interferon-gamma production in perfusion culture of CHO cells.

The importance of cell cycle analysis in cell culture development has been widely recognised. Whether such analysis is useful in indicating future performance of high cell density culture is uncertain. Using flow cytometric approach to address this question, we utilised the fraction of cells in the S phase to control specific growth rate and productivity in spin filter perfusion cultures and found a significant increase in the accumulated interferon-gamma over that obtained from the nutrient-based controlled fed culture. While a general decrease with time exists in both percentage of S phase cells and specific growth rate, a clear oscillatory behaviour of both parameters is found in perfusion cultures.